Production method of electronic device having internal electrode

ABSTRACT

A release layer  22  is formed on a surface of a first supporting sheet  20.  Next, an electrode layer  12   a  is formed on a surface of the release layer  22.  When the electrode layer  12   a  is pressed against a surface of a green sheet  10   a  to bond the electrode layer  12   a  with the green sheet  10   a,  an adhesive layer  28  is formed by a transfer method on a surface of the electrode layer  12   a  or a surface of the green sheet  10   a.  It becomes possible to easily transfer a dry type electrode layer to the surface of the green sheet with high accuracy without breaking or deforming the green sheet, moreover, components of the adhesive layer do not soak in the electrode layer or green sheet. Also, the supporting sheet is extremely easily released, and a production cost of a multilayer ceramic capacitor is reduced.

TECHNICAL FIELD

The present invention relates to a production method of a multilayerelectronic device having an internal electrode, such as a multilayerceramic capacitor.

BACKGOUND ART

In recent years, along with a variety of electronic apparatuses becomingmore compact, an electronic device to be installed in an electronicapparatus has become more compact and higher in performance. Amultilayer ceramic capacitor as one of the electronic devices is alsoexpected to be more compact and higher in performance.

For pursuing a more compact multilayer ceramic capacitor having a largercapacity, there has been a strong demand for a thinner dielectric layer.Recently, a thickness of a dielectric green sheet has come to several μmor thinner.

To produce a ceramic green sheet, ceramic slurry made by ceramic powder,a binder (an acrylic based resin and a butyral resin, etc.), aplasticizer and an organic solvent (toluene, alcohol and MEK, etc.) isnormally prepared first, then, the ceramic slurry is applied to acarrier sheet, such as PET, by using the doctor blade method, etc. anddried by heating.

Also, in recent years, a production method of preparing ceramicsuspension obtained by mixing ceramic powder and a binder in a solvent,and performing 2-dimensional drawing on a film-shaped mold obtained byextrusion molding of the suspension has been studied.

A method of producing a multilayer ceramic capacitor by using theceramic green sheet explained above will be explained specifically. Aninternal electrode conductive paste including metal powder and a binderis printed to be a predetermined pattern on the ceramic green sheet anddried to form an internal electrode pattern. Next, a carrier sheet isreleased from the ceramic green sheet, a plurality of the results arestacked and cut to be a chip shape, so that a green chip is obtained.Next, after firing the green chip, an external electrode is formed, andthe multilayer ceramic capacitor is produced.

However, in the case of printing the internal electrode paste on anextremely thin ceramic green sheet, there is a disadvantage that abinder component in the ceramic green sheet is dissolved or swollen dueto a solvent in the internal electrode paste. Also, there is adisadvantage that an internal electrode paste soaks in the green sheet.These disadvantages often cause a short-circuiting defect.

To eliminate the disadvantages, in articles 1 to 3 (the JapaneseUnexamined Patent Publication Nos. 63-51616, 3-250612 and 7-312326), adry type electrode pattern is separately prepared by forming an internalelectrode pattern on a supporting sheet and drying the same. An internalelectrode pattern transfer method for transferring the dry typeelectrode pattern to a surface of each ceramic green sheet or a surfaceof a multilayer body of ceramic green sheets has been proposed.

In the techniques described in the articles 1 and 2, an electrodepattern is formed by printing on a supporting film and thermal transferis performed, however, there is a problem that the electrode pattern ishard to be released from the supporting film.

Also, in consideration of releasability and transferability in astacking step, in a normal ceramic green sheet, a dielectric pastecomposing the green sheet is added with a release agent, or a releaseagent is coated on a supporting sheet to be formed with the green sheet.Accordingly, when the ceramic green sheet is particularly thin, theceramic green sheet on the supporting sheet has very weak strength andis in a brittle state. Alternately, the ceramic green sheet on thesupporting sheet easily deviates from the supporting sheet. Therefore,it is extremely difficult to transfer a dry type electrode pattern to asurface of the green sheet with high accuracy, and the ceramic greensheet is partially broken in the transfer step in some cases.

Also, in the technique described in the article 3, a layer exclusive forforming an electrode pattern and a rear-transfer prevention layer, etc.are formed to prevent cissing, etc. of an electrode pattern at the timeof forming a release layer on a supporting sheet to be formed with a drytype electrode pattern. In this method, it is expected that transfer ofthe electrode pattern to a surface of a green sheet becomes easy,however, it is not sufficient and a problem of increasing a productioncost of the supporting sheet remains.

Also, in the transfer method according to these conventional techniques,since a high pressure and heat are necessary to transfer the electrodepattern layer to the surface of the green sheet, the green sheet,electrode layer and supporting sheet often deform and become unable tobe used at the time of stacking, and there is a possibility of causing ashort-circuiting defect due to break of the green sheet.

Also, when bonding the green sheet with the electrode layer, it wasdifficult to selectively peel off one of two supporting sheets forrespectively supporting the both.

Note that a method of forming an adhesive layer on a surface of theelectrode layer or green sheet is considered for easier transfer of theelectrode layer. However, when forming an adhesive layer directly on thesurface of the electrode layer or green sheet by a coating method, etc.,components of the adhesive layer soak in the electrode layer or greensheet. Therefore, a function as an adhesive layer is hard to beattained, and it is liable that a composition of the electrode layer orgreen sheet is adversely affected.

DISCLOSURE OF THE INVENTION

The present invention was made in consideration of the abovecircumstances and has as an object thereof to provide a productionmethod of a multilayer electronic device including an internalelectrode, by which a green sheet is not damaged or deformed, componentsof an adhesive layer do not soak in an electrode layer or the greensheet, a dry type electrode layer can be easily transferred to a surfaceof the green sheet with high accuracy, moreover, a supporting sheet isextremely easily released, and the cost is reduced.

The present inventors have been committed themselves to study forattaining the above objects, found that, by forming an adhesive layer ona surface of an electrode layer or green sheet by a transfer method, athickness of an adhesive layer can be made thin and, furthermore,components of the adhesive layer do not soak in the electrode layer orgreen sheet, and the object of the present invention can be attained,and completed the present invention.

Namely, according to the present invention, a production method of aelectronic device including an internal electrode comprises the steps of

forming a release layer on a surface of a first supporting sheet;

forming an electrode layer on a surface of said release layer;

pressing said electrode layer against a surface of a green sheet to bondsaid electrode layer with the surface of said green sheet;

stacking the green sheets bonded with said electrode layer to form agreen chip; and

firing said green chip;

wherein

before pressing said electrode layer against the surface of said greensheet, an adhesive layer is formed on a surface of said electrode layeror a surface of said green sheet by a transfer method.

Preferably, said green sheet is formed on a surface of a secondsupporting sheet in a releasable way and, after said electrode layer isbonded with a surface of said green sheet, said second supporting sheetis released from the surface of said green sheet.

Preferably, said adhesive layer is formed on a surface of a thirdsupporting sheet in a releasable way first and pressed against a surfaceof said green sheet or a surface of said electrode layer so as to bebonded.

In the production method of electronic device having an internalelectrode according to the present invention, an adhesive layer isformed by a transfer method on a surface of an electrode layer or greensheet and the electrode layer is bonded with a surface of the greensheet via the adhesive layer. By forming the adhesive layer, a highpressure and heat become unnecessary at the time of bonding theelectrode layer with the surface of the green sheet for transferring,and bonding at a lower pressure and lower temperature becomes possible.Accordingly, even in the case of an extremely thin green sheet, thegreen sheet is not broken, green sheets bonded with an internalelectrode can be preferably stacked, and short-circuiting defect, etc.are not caused.

Also, for example, by making an adhesive force of the adhesive layerstronger than that of the release layer and making an adhesive force ofthe release layer stronger than that between the green sheet andsupporting sheet, the supporting sheet on the green sheet side can beselectively released easily.

Furthermore, according to the present invention, since the adhesivelayer is not formed directly on the surface of the electrode layer orgreen sheet by a coating method, etc. but formed by a transfer method,components of the adhesive layer do not soak in the electrode layer orgreen sheet and an extremely thin adhesive layer can be formed. Forexample, a thickness of said adhesive layer can be made thin as 0.02 to0.3 μm or so. Although the thickness of the adhesive layer is thin,components of the adhesive layer do not soak in the electrode layer orgreen sheet, so that the adhesive force is sufficient and a compositionof the electrode layer or green sheet is not adversely affected.

Preferably, to form said green chip, a step of pressing anotherelectrode layer to be bonded against an opposite surface of theelectrode layer side of the green sheet bonded with said electrode layerso as to bond the electrode layer via an adhesive layer formed by thetransfer method, and a step of pressing the electrode layer againstanother green sheet so as to bond via an adhesive layer formed by thetransfer method are repeated.

Alternately, to form said green chip, a step of pressing another greensheet to be bonded against a surface on the electrode layer side of thegreen sheet bonded with said electrode layer so as to bond the greensheet via an adhesive layer formed by the transfer method, and a step ofpressing another electrode layer against the green sheet so as to bondvia an adhesive layer formed by the transfer method may be repeated.

By repeating the above steps, an electronic device, such as a multilayerceramic capacitor having a large number of layers, can be easilyproduced.

Preferably, a thickness of said adhesive layer is 0.02 to 0.3 μm. When athickness of the adhesive layer is too thin, a thickness of the adhesivelayer becomes thinner than asperity on the green sheet surface, andadhesiveness tends to decline remarkably. While, when a thickness of theadhesive layer is too thick, spaces easily arise inside an element bodyafter sintering depending on the thickness of the adhesive layer andcapacitance tends to decline remarkably by an amount of the volume.

Preferably, said electrode layer is formed to be a predetermined patternon a surface of said release layer, and a blank pattern layer havingsubstantially the same thickness as that of said electrode layer isformed on a surface of the release layer not formed with the electrodelayer. Preferably, said blank pattern layer includes substantially thesame dielectrics as that composing said green sheet. Preferably, saidblank pattern layer includes substantially the same binder as that ofsaid green sheet.

By forming a blank pattern layer, a level difference on the surface dueto an electrode layer having a predetermined pattern can be eliminated.Therefore, even if a pressure is applied before firing after stacking alarge number of green sheets, an outer surface of a stacked body remainsflat, positional deviation in the plane direction of the electrode layeris not caused, moreover, green sheet is not staved in to causeshort-circuiting.

Preferably, said release layer includes substantially the samedielectrics as that composing said green sheet. In that case, even ifthe release layer adheres to the surface of the electrode layer toremain, the remaining release layer does not cause any problem. It isbecause the remaining release layer is sufficiently thin comparing withthe green sheet and includes the same dielectric as that composing thegreen sheet, so that it becomes a part of the dielectric layer in thesame way as the green sheet if stacked with the green sheet and firedtogether.

Preferably, said release layer includes substantially the same binderresin as that included in said green sheet. Preferably, said adhesivelayer includes substantially the same binder resin as that included insaid green sheet. Preferably, said electrode layer includessubstantially the same binder resin as that included in said greensheet.

By using the same binder resin as above, a stronger adhesive force canbe obtained comparing with the case of using two or more kinds of binderresins.

Furthermore preferably, said binder resin includes a butyral based resinas a part thereof or is composed only of a butyral based resin. When thebinder resin is a specific butyral based resin, a green sheet can bemade thinner and preferably bonded with a low pressure.

Also, the release layer, adhesive layer, electrode layer and green sheetmay include a plasticizer with a binder resin, and the plasticizer isincluded preferably by 25 to 100 parts by weight with respect to 100parts by weight of the binder resin.

Preferably, a thickness of said green sheet is 3 μm or thinner. Inaccordance with the present invention, the green sheet of 3 μm orthinner can be stacked easily.

Preferably, the thickness of the release layer is the same or less thanthe thickness of the electrode layer. The thickness of the release layeris set to be preferably 60% and more preferably 30% of a thickness ofthe electrode layer. The lower limit of the release layer thickness isdetermined by a particle diameter, etc. of a dielectric material able tobe used for the release layer and is preferably 0.05 to 0.01 μm.

Preferably, a pressure at the time of bonding the electrode layer with asurface of the green sheet is 0.2 to 15 MPa, more preferably 0.2 to 6MPa, and particularly preferably 1 to 3 MPa. Also, the temperature atpressing is preferably 40 to 100° C. or so, and more preferably 90° C.or lower. Furthermore, when a supporting sheet of the green sheet is anorganic film, it is preferable that the temperature is not higher thanthe glass transition temperature of the organic film.

When the pressuring temperature is too low, it is liable that transferbecomes difficult, while when too high, it is liable that thermaldeformation arises on the supporting sheet and it becomes difficult totransfer an electrode layer having a predetermined pattern to a greensheet with high accuracy. Also, when a pressuring force is too small, itis liable that transfer becomes difficult, while when too large,possibility of breaking the green sheet becomes high and unfavorable.Particularly, when a thickness of the green sheet is thin, it ispreferable that the electrode layer can be bonded with a surface of thegreen sheet with a small pressuring force. Note that pressuring by apair of rolls is preferable.

In the present invention, preferably, the electrode layer is formed on asurface of the release layer by a thick film method using an electrodepaste. The thick film method is not particularly limited and a screenprinting, etc. may be mentioned. Note that the film may be formed by athin film method on the surface of the release layer. The thin filmmethod is not particularly limited and the sputtering method, the vacuumevaporation method and the CVD method, etc. may be mentioned.

When forming an electrode layer by the thin film methods, a binder andplasticizer components evaporate in vacuum and the release layer on thesurface of the first supporting sheet is damaged by sputtering particlesand evaporated particles. However, this affects to reduce the releaselayer strength, so that it is preferable for transferring the electrodelayer to the surface of the green sheet.

Note that, in the present invention, a material and a production method,etc. of the green sheet are not particularly limited, and a ceramicgreen sheet formed by the doctor blade method and a porous ceramic greensheet obtained by performing 2-dimensional drawing on a film formed byextrusion molding may be used.

Also, in the present invention, a concept of an electrode layer includesan electrode paste film to be an internal electrode layer after firing.

BRIEF DESCRIPTION OF DRAWINGS

Below, the present invention will be explained based on embodimentsshown in drawings, wherein:

FIG. 1 is a schematic sectional view of a multilayer ceramic capacitoraccording to an embodiment of the present invention;

FIG. 2A to FIG. 2C and FIG. 3A to FIG. 3C are sectional views of a keypart showing a transfer method of an electrode layer; and

FIG. 4A to FIG. 4C, FIG. 5A to FIG. 5C and FIG. 6A to FIG. 6C aresectional views of a key part showing a stacking method of a green sheetbonded with an electrode layer.

BEST MODE FOR CARRYING OUT THE INVENTION

Below, the present invention will be explained in detail based onembodiments shown in the drawings.

First, as an embodiment of an electronic device produced by a methodaccording to the present invention, an overall configuration of amultilayer ceramic capacitor will be explained.

As shown in FIG. 1, a multilayer ceramic capacitor 2 according to thepresent embodiment comprises a capacitor element 4, a first terminalelectrode 6 and a second terminal electrode 8. The capacitor element 4has dielectric layers 10 and internal electrode layers 12, and theinternal electrode layers 12 are alternately stacked between thedielectric layers 10. One side of the alternately stacked internalelectrode layers 12 is electrically connected to inside the firstterminal electrode 6 formed outside of one end portion of the capacitorelement body 4. Also, the other side of the alternately stacked internalelectrode layers 12 is electrically connected to inside of the secondterminal electrode 8 formed outside of the other end portion of thecapacitor element body 4.

In the present embodiment, the internal electrode layer 12 is formed bytransferring an electrode layer 12 a to a ceramic green sheet 10 a asshown in FIG. 2 to FIG. 6 and composed of the same material as that ofthe electrode layer 12 a, and a thickness thereof is thicker than theelectrode layer 12 a exactly by an amount of contraction in thehorizontal direction due to firing, which will be explained later on.

A material of the dielectric layer 10 is not particularly limited andformed by a dielectric material, such as calcium titanate, strontiumtitanate and/or barium titanate. A thickness of each dielectric layer 10is not particularly limited but generally several μm to several hundredsof μm. Particularly, in the present embodiment, the layer is made thinas preferably 5 μm or thinner and more preferably 3 μm or thinner.

Also, a material of the terminal electrodes 6 and 8 is not particularlylimited and normally copper, a copper alloy, nickel and nickel alloy,etc. are normally used and silver or silver alloy with palladium, etc.can be also used. Also, a thickness of the terminal electrodes 6 and 8is not particularly limited and is normally 10 to 50 μm or so.

A shape and size of the multilayer ceramic capacitor 2 may be suitablydetermined in accordance with the use object. When the multilayerceramic capacitor 2 is rectangular parallelepiped, it is normally alength (0.6 to 5.6 mm, preferably 0.6 to 3.2 mm)×width (0.3 to 5.0 mm,preferably 0.3 to 1.6 mm)×thickness (0.1 to 1.9 mm, preferably 0.3 to1.6 mm) or so.

Next, an example of a production method of the multilayer ceramiccapacitor 2 according to the present embodiment will be explained.

(1) First, a dielectric paste is prepared to produce a ceramic greensheet to compose the dielectric layer 10 shown in FIG. 1 after firing.

The dielectric paste is normally composed of an organic solvent basedpaste obtained by kneading a dielectric material with an organicvehicle, or a water based paste.

The dielectric material may be suitably selected from a variety ofcompounds to be a composite oxide or oxide, such as carbonate, nitrate,hydroxide and organic metal compound, and mixed to be used. Thedielectric material is normally used as particles having an averageparticle diameter of 0.1 to 3.0 μm or so. Note that it is preferable touse finer powder than a green sheet thickness to form an extremely thingreen sheet.

The organic vehicle is obtained by dissolving a binder in an organicsolvent. The binder used for the organic vehicle is not particularlylimited and a variety of normal binders, such as ethyl cellulose,polyvinyl butyral, and an acrylic resin. Preferably, polyvinyl butyraland other butyral based resin are used.

Also, the organic solvent to be used for the organic vehicle is notparticularly limited and an organic solvent, such as terpineol, butylcarbitol, acetone and toluene, is used. Also, the vehicle in the waterbased paste is obtained by dissolving a water-soluble binder in water.The water-soluble binder is not particularly limited and polyvinylalcohol, methyl cellulose, hydroxyl ethyl cellulose, a water-solubleacrylic resin, and emulsion, may be used. A content of each component inthe dielectric paste is not particularly limited and may be a normalcontent, for example, the binder by 1 to 5 wt % or so and the solvent(or water) by 10 to 50 wt % or so.

The dielectric paste may include additives selected from a variety ofdispersants, plasticizers, dielectrics, glass flits and insulators. Notethat a total content of these is preferably 10 wt % or smaller. Whenusing a butyral based resin as a binder resin, a content of aplasticizer is preferably 25 to 100 parts by weight with respect to 100parts by weight of the binder resin. When the plasticizer is too little,the green sheet tends to become brittle, while when too much, theplasticizer exudes to decline the handlability.

By using the dielectric paste, a green sheet 10 a is formed to be athickness of preferably 0.5 to 30 μm, and more preferably 0.5 to 10 μmor so on a carrier sheet 30 as a second supporting sheet as shown inFIG. 3A by the doctor blade method, etc. The green sheet 10 a is driedafter being formed on the carrier sheet 30. The drying temperature ofthe green sheet 10 a is preferably 50 to 100° C. and the drying time ispreferably 1 to 20 minutes. A thickness of the green sheet 10 a afterdrying is reduced to 5 to 25% of a thickness before drying.

(2) A carrier sheet 20 as a first supporting sheet is preparedseparately from the above carrier sheet 30 as shown in FIG. 2A, arelease layer 22 is formed thereon, an electrode layer 12 a having apredetermined pattern is formed thereon, and adjacent thereto, a blankpattern layer 24 having substantially the same thickness as that of theelectrode layer 12 a is formed on a surface of the release layer 22 notformed with the electrode layer 12 a.

As the carrier sheets 20 and 30, for example, a PET film, etc. is used,which is preferably coated with silicon, etc. to improve thereleasability. A thickness of the carrier sheets 20 and 30 is notparticularly limited and preferably 5 to 100 μm. Thicknesses of thecarrier sheets 20 and 30 may be the same or different.

The release layer 22 preferably includes the same dielectric particlesas that in the dielectrics composing the green sheet 10 a shown in FIG.3A. Also, the release layer 22 includes a binder, plasticizer and,optionally, a release agent other than the dielectric particles. Aparticle diameter of the dielectric particles may be the same as that ofthe dielectric particles included in the green sheet, but is preferablysmaller.

In the present embodiment, a thickness t2 of the release layer 22 ispreferably thinner than a thickness of the electrode layer 12 a and isset to have a thickness of preferably 60% or less, and more preferably30% or less.

The coating method of the release layer 22 is not particularly limitedbut a coating method using, for example, a wire bar coater is preferablebecause it is necessary to form it extremely thin. Note that adjustmentof the thickness of the release layer can be made by selecting a wirebar coater having a different wire diameter. Namely, to make thethickness of the release layer to be applied thinner, it can be done byselecting one having a small wire diameter, inversely, to form it thick,one with a large wire diameter may be selected. The release layer 22 isdried after being applied. The drying temperature is preferably 50 to100° C. and the drying time is preferably 1 to 10 minutes.

A binder for the release layer 22 is composed, for example, of anacrylic resin, polyvinyl butyral, polyvinyl acetal, polyvinyl alcohol,polyolefin, polyurethane, polystyrene, or an organic composed of acopolymer of these or emulsion. The binder contained in the releaselayer 22 may be the same as the binder contained in the green sheet 10 aor may be different from that, but preferably the same.

A plasticizer for the release layer 22 is not particularly limited and,for example, phthalate ester, adipic acid, phosphate ester and glycols,etc. may be mentioned. The plasticizer to be contained in the releaselayer 22 may be the same as that contained in the green sheet 10 a ormay be different from that.

A release agent for the release layer 22 is not particularly limitedand, for example, paraffin, wax and silicone oil, etc. may be mentioned.A release agent contained in the release layer 22 may be the same asthat contained in the green sheet 10 a or may be different from that.

A binder is contained in the release layer 22 by preferably 2.5 to 200parts by weight, more preferably 5 to 30 parts by weight, andparticularly preferably 8 to 30 parts by weight or so with respect to100 parts by weight of dielectric particle.

A plasticizer is preferably contained in the release layer 22 by 0 to200 parts by weight, preferably 20 to 200 parts by weight, and morepreferably 50 to 100 parts by weight with respect to 100 parts by weightof the binder.

A release agent is preferably contained in the release layer 22 by 0 to100 parts by weight, preferably 2 to 50 parts by weight, and morepreferably 5 to 20 parts by weight with respect to 100 parts by weightof the binder.

After forming the release layer 22 on the surface of the carrier sheet30, as shown in FIG. 2A, an electrode layer 12 a to compose an internalelectrode layer 12 after firing is formed to be a predetermined patternon the surface of the release layer 22. A thickness of the electrodelayer 12 a is preferably 0.1 to 2 μm, and more preferably 0.1 to 1.0 μmor so. The electrode layer 12 a may be configured by a single layer ortwo or more layers having different compositions.

The electrode layer 12 a can be formed on the surface of the releaselayer 22 by a thick film formation method, such as a printing methodusing an electrode paste, or a thin film method, such as evaporation andsputtering. When forming the electrode layer 12 a on the surface of therelease layer 22 by a screen printing method or a gravure printingmethod as a kind of thick film method, it is as follows.

First, an electrode paste is prepared. The electrode paste is fabricatedby kneading a conductive material composed of a variety of conductivemetals and alloys, or a variety of oxides, organic metal compounds orresinates, etc. to be conductive materials after firing, with an organicvehicle.

As a conductive material to be used when producing the electrode paste,Ni, a Ni alloy and a mixture of these are used. A shape of theconductive materials is not particularly limited and may be a sphericalshape and scale-like shape, etc. or a mixture of these shapes. Thosehaving an average particle diameter of the conductive material ofnormally 0.1 to 2 μm, and preferably 0.2 to 1 μm or so may be used.

An organic vehicle contains a binder and a solvent. As the binder, forexample, ethyl cellulose, an acrylic resin, polyvinyl butyral, polyvinylacetal, polyvinyl alcohol, polyolefin, polyurethane, polystyrene, or acopolymer of these may be mentioned. Particularly, butyrals, such aspolyvinyl butyral, are preferable.

The binder is contained in the electrode paste by preferably 4 to 20parts by weight with respect to 100 parts by weight of the conductivematerial (metal powder). As a solvent, any of well-known ones, such asterpineol, butylcarbitol and kerosene, may be used. A content of thesolvent is preferably 20 to 55 wt % or so with respect to the entirepaste.

To improve the adhesiveness, the electrode paste preferably contains aplasticizer. As a plasticizer, benzylbutyl phthalate (BBP) and otherphthalate esters, adipic acids, phosphoric esters, and glycols, etc. maybe mentioned. The plasticizer in the electrode paste is preferably 10 to300 parts by weight, and more preferably 10 to 200 parts by weight withrespect to 100 parts by weight of the binder. Alternately, the electrodepaste is added with an acrylic binder (lauryl methacrylate, ethylhexylmethacrylate, lauryl acrylate, ethylhexyl acrylate and butyl acrylate,etc.) having a glass transition temperature Tg of not higher than theroom temperature is added preferably by 10 to 100 parts by weight withrespect to 100 parts by weight of the binder. Furthermore, in the sameway, an adhesive may be added to the electrode paste by 100 parts byweight or less with respect to 100 parts by weight of the binder. Notethat when an adding quantity of the plasticizer or adhesive is toolarge, strength of the electrode layer 12 a tends to decline remarkably.Also, to improve transferability of the electrode layer 12 a, it ispreferable to improve adhesiveness and/or adherence of the electrodepaste by adding a plasticizer and/or adhesive to the electrode paste.

The adhesive is not particularly limited and, for example, butylacrylate (BA), 2-ethylhexyl acrylate (2HEA) and lauryl methacrylate(RMA) may be mentioned.

After or before forming the electrode paste layer having a predeterminedpattern on the surface of the release layer 22 by a printing method, ablank pattern layer 24 is formed to be substantially the same thicknessas that of the electrode layer 12 a on the surface of the release layer22 not formed with the electrode layer 12 a. The blank pattern layer 24is composed of the same material as that of the green sheet 10 a shownin FIG. 3A and formed by the same method. The electrode layer 12 a andthe blank pattern layer 24 are dried in accordance with need. The dryingtemperature is not particularly limited, but is preferably 70 to 120°C., and the drying time is preferably 5 to 15 minutes.

(3) As shown in FIG. 2A, an adhesive layer transfer sheet formed with anadhesive layer 28 is prepared on the surface of a carrier sheet 26 as athird supporting sheet separately from the carrier sheets 20 and 30explained above. The carrier sheet 26 is formed by the same sheet asthat of the carrier sheets 20 and 30.

A composition of the adhesive layer 28 is the same as that of therelease layer 22 except for not containing dielectric particles. Namely,the adhesive layer 28 contains a binder, a plasticizer and a releaseagent. The adhesive layer 28 may contain the same dielectric particlesas that of the dielectrics composing the green sheet 10 a, however, inthe case of forming an adhesive layer having a thinner thickness than aparticle diameter of the dielectric particles, it is better not tocontain dielectric particles. Also, when dielectric particles arecontained in the adhesive layer 28, a ratio of the dielectric particleswith respect to the binder weight is preferably smaller than a ratio ofthe dielectric particles contained in the green sheet with respect tothe binder weight.

The binder and a plasticizer for the adhesive layer 28 are preferablythe same as those in the release layer 22, but it may be different fromthem.

A plasticizer is preferably contained in the adhesive layer 28 by 0 to200 parts by weight, preferably 20 to 200 parts by weight, and morepreferably 20 to 100 parts by weight with respect to 100 parts by weightof the binder.

A thickness of the adhesive layer 28 is preferably 0.02 to 0.3 μm or so.When a thickness of the adhesive layer 28 is too thin, the adhesiveforce declines, while when too thick, it is liable to cause a defect(spaces).

The adhesive layer 28 is formed on the surface of the carrier sheet 26as a third supporting sheet, for example, by a bar coater method, diecoater method, reverse coater method, dip coater method and kiss coatermethod, etc. and dried in accordance with need. The drying temperatureis not particularly limited, but is preferably the room temperature to80° C., and the drying time is preferably 1 to 5 minutes.

(4) To form the adhesive layer on the surface of the electrode layer 12a and the blank pattern layer 24 shown in FIG. 2A, a transfer method isapplied in the present embodiment. Namely, as shown in FIG. 2B, theadhesive layer 28 of the carrier sheet 26 is pressed against the surfaceof the electrode layer 12 a and the blank pattern layer 24, heated andpressed, then, the carrier sheet 26 is removed. Consequently, as shownin FIG. 2C, the adhesive layer 28 is transferred to the surface of theelectrode layer 12 a and the blank pattern layer 24.

The heating temperature at that time is preferably 40 to 100° C., andthe pressing force is preferably 0.2 to 15 MPa. Pressing may beperformed by a press or a calendar roll, but is preferably performed bya pair of rolls.

After that, the electrode layer 12 a is bonded with the surface of thegreen sheet 10 a formed on the surface of the carrier sheet 30 shown inFIG. 3A. For that purpose, as shown in FIG. 3B, the electrode layer 12 aand the blank pattern layer 24 of the carrier sheet 20 are pressedagainst the surface of the green sheet 10 a together with the carriersheet 20 via the adhesive layer 28, heated and pressed. As a result, asshown in FIG. 3C, the electrode layer 12 a and the blank pattern layer24 are transferred to the surface of the green sheet 10 a. Note thatsince the carrier sheet 30 on the green sheet side is peeled off, whenseeing from the green sheet 10 a side, the green sheet 10 a istransferred to the electrode layer 12 a and the blank pattern layer 24via the adhesive layer 28.

Heating and pressing at the time of transferring may be pressing andheating by a press or by a calendar roll, but is preferably performed bya pair of rolls. The heating temperature and the pressing force are sameas those at the time of transferring the adhesive layer 28.

A single-layer electrode layer 12 a having a predetermined pattern isformed on the single green sheet 10 a by steps shown in FIG. 2A to FIG.3C. A green sheet 10 a formed with the electrode layer 12 a is stacked,for example, by repeating the steps shown in FIG. 4A to FIG. 6C. Notethat, in FIG. 4A to FIG. 6C, the same reference numbers are given tocommon members with those shown in FIG. 3A to FIG. 4C, and anexplanation thereon is partially omitted.

First, as shown in FIG. 4A to FIG. 4C, the adhesive layer 28 istransferred to the surface on the other side of the electrode layer(back side) on the green sheet 10 a. After that, as shown in FIG. 5A toFIG. 5C, the electrode layer 12 a and the blank pattern layer 24 aretransferred to the back side of the green sheet 10 a via the adhesivelayer 28.

Next, as shown in FIG. 6A to FIG. 6C, on the surface of the electrodelayer 12 a and the blank pattern layer 24, the green sheet 10 a istransferred via the adhesive layer 28. After that, by repeating thetransfer, a multilayer body, wherein a large number of electrode layers12 a and the green sheet 10 a are alternately stacked, is obtained.

Then, after performing final pressing on the stacked body, the carriersheet 20 is peeled off. Pressure at the time of the final pressing ispreferably 10 to 200 MPa. The heating temperature is preferably 40 to100° C. After that, the multilayer body is cut to be a predeterminedsize to form green chips. The green chips are subjected to binderremoval processing and firing processing, then, thermal treatment isperformed in order to re-oxidize the dielectric layer.

The binder removal processing may be performed under a normal condition,but when using a base metal, such as Ni and a Ni alloy, as a conductivematerial of the internal electrode layer, it is preferably performedunder the specific condition below.

temperature rising rate: 5 to 300° C./hour, particularly 10 to 50°C./hour

holding temperature: 200 to 400° C., particularly 250 to 350° C.

holding time: 0.5 to 20 hours, particularly 1 to 10 hours

atmosphere: a wet mixed gas of N₂ and H₂

A firing condition is preferably as below.

temperature rising rate: 50 to 500° C./hour, particularly 200 to 300°C./hour

holding temperature: 1100 to 1300° C., particularly 1150 to 1250° C.

holding time: 0.5 to 8 hours, particularly 1 to 3 hours

cooling rate: 50 to 500° C./hour, particularly 200 to 300° C./hour

atmosphere gas: a wet mixed gas of N₂ and H₂, etc.

Note that oxygen partial pressure in an atmosphere in the air at firingis preferably 10⁻² Pa or lower, particularly 10⁻² to 10⁻⁸ Pa. Whenexceeding the above ranges, the internal electrode layer tends tooxidize, while when the oxygen partial pressure is too low, it is liablethat abnormal sintering is caused in an electrode material of theinternal electrode layer to be broken.

The thermal treatment after performing such firing is preferablyperformed with a holding temperature or highest temperature of 1000° C.or higher, more preferably 1000 to 1100° C. When the holding temperatureor the highest temperature at the time of the thermal treatment is lowerthan the above ranges, it is liable that oxidization of the dielectricmaterial is insufficient to make the insulation resistance lifetimeshort, while when exceeding the above ranges, Ni in the internalelectrode oxidizes and the capacity decreases, moreover, Ni reacts witha dielectric base and the lifetime also tends to become short. Theoxygen partial pressure at the time of thermal treatment is higher thanthat in a reducing atmosphere at the time of firing, preferably 10⁻³ Pato 1 Pa, and more preferably 10⁻² Pa to 1 Pa. When it is lower than theabove range, re-oxidization of the dielectric layer 2 becomes difficult,while when exceeding the above ranges, the internal electrode layer 3tends to oxidize. Other condition of the thermal treatment is preferablyas below.

holding time: 0 to 6 hours, particularly 2 to 5 hours

cooling rate: 50 to 500° C./hour, particularly 100 to 300° C./hour

atmosphere gas: wet N₂ gas, etc.

Note that to wet a N₂ gas or a mixed gas, etc., for example, a wetter,etc. may be used. In this case, the water temperature is preferably 0 to75° C. or so. Also, the binder removal processing, firing and thermaltreatment may be performed continuously or separately. When performingcontinuously, the atmosphere is changed without cooling after the binderremoval processing, continuously, the temperature is raised to theholding temperature at firing to perform firing. Next, it is cooled andthe thermal treatment is preferably performed by changing the atmospherewhen the temperature reaches to the holding temperature of the thermaltreatment. On the other hand, when performing them separately, afterraising the temperature to the holding temperature at the binder removalprocessing in an atmosphere of a N₂ gas or a wet N₂ gas, the atmosphereis changed, and the temperature is furthermore raised. After that, aftercooling the temperature to the holding temperature at the thermaltreatment, it is preferable that the cooling continues by changing theatmosphere again to a N₂ gas or a wet N₂ gas. Also, in the thermaltreatment, after raising the temperature to the holding temperatureunder the N₂ gas atmosphere, the atmosphere may be changed, or theentire process of the thermal processing may be in a wet N₂ gasatmosphere.

The thus obtained sintered body (element body 4) is subjected to endsurface polishing, for example, by barrel polishing and sand-blast,etc., then, a terminal electrode paste is burnt to form terminalelectrodes 6 and 8. For example, a firing condition of the terminalelectrode paste is preferably in a wet mixed gas of N₂ and H₂ at 600 to800° C. for 10 minutes to 1 hour or so. In accordance with need,soldering, etc. is performed on the terminal electrodes 6 and 8 to forma pad layer. Note that the terminal electrode paste may be fabricated inthe same way as the electrode paste explained above.

A multilayer ceramic capacitor of the present invention produced asabove is mounted on a print substrate, etc. by soldering, etc. and usedfor a variety of electronic equipments, etc.

In a method of producing a multilayer ceramic capacitor according to thepresent embodiment, it is possible to easily transfer a dry typeelectrode layer 12 a to a surface of the green sheet 10 a with highaccuracy without breaking or deforming the green sheet 10 a.

Particularly, in the production method of the present embodiment, theadhesive layer 28 is formed on the surface of the electrode layer orgreen sheet by the transfer method, and the electrode layer 12 a isbonded with the surface of the green sheet 10 a via the adhesive layer28. By forming the adhesive layer 28, a high pressure and heat becomeunnecessary at the time of bonding the electrode layer 12 a to transferto the surface of the green sheet 10 a, so that bonding at a lowerpressure and lower temperature becomes possible. Accordingly, even inthe case of an extremely thin green sheet 10 a, the green sheet 10 a isnot broken, the electrode layers 12 a and green sheets 10 a can bepreferably stacked, and short-circuiting defect, etc. are not caused.

Also, for example, by making an adhesive force of the adhesive layer 28stronger than that of the release layer 22 and making an adhesive forceof the release layer 22 stronger than that between the green sheet 10 aand the carrier sheet 30, etc., the carrier sheet 30 on the green sheet10 a side can be selectively released easily.

Furthermore, in the present embodiment, the adhesive layer 28 is notdirectly formed on a surface of the electrode layer 12 a or green sheet10 a by a coating method, etc. and formed by a transfer method, so thatcomponents of the adhesive layer 28 do not soak in the electrode layer12 a or green sheet 10 a, and it becomes possible to form an extremelythin adhesive layer 28. For example, a thickness of the adhesive layer28 can be made thin as 0.02 to 0.3 μm or so. Although the thickness ofthe adhesive layer 28 is thin, components of the adhesive layer 28 donot soak in the electrode layer 12 a and green sheet 10 a, the adhesiveforce is sufficient and a composition of the electrode layer 12 a orgreen sheet 10 a is not adversely affected.

Note that the present invention is not limited to the above embodimentsand may be variously modified within the scope of the present invention.

For example, the method of the present invention is not limited to theproduction method of the multilayer ceramic capacitor but can be appliedas a production method of other multilayer electronic device includingan internal electrode.

Below, the present invention will be explained based on further detailedexamples, but the present invention is not limited to the examples.

EXAMPLE 1

First, each paste below was prepared.

Green Sheet Paste (as same as Blank Pattern Paste)

Powders selected from BaTiO₃ powder (BT-02 made by Sakai ChemicalIndustry Co., Ltd.), MgCO₃, MnCO₃, (Ba_(0.6)Ca_(0.4))SiO₃ and rareearths (Gd₂O₃, Tb₄O₇, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, Lu₂O₃, andY₂O₃) were wet mixed by a ball mill for 16 hours and dried to obtain adielectric material. An average particle diameter of the materialpowders was 0.1 to 1 μm.

(Ba_(0.6)Ca_(0.4))SiO₃ was produced by wet mixing BaCO₃, CaCO₃ and SiO₂by a ball mill for 16 hours, dried and fired at 1150° C. in the air, andwet grinding the result for 100 hours by a ball mill.

To make the dielectric material paste, an organic vehicle was added tothe dielectric material and mixed by a ball mill and a dielectric greensheet paste was obtained. The organic vehicle has a blending ratio of 6parts by weight of polyvinyl butyral as a binder, 3 parts by weight ofbis(2-ethylhexyl) phthalate (DOP), 55 parts by weight of ethyl acetateand 10 parts by weight of toluene as a plasticizer, and 0.5 part byweight of paraffin as a release agent with respect to 100 parts byweight of the dielectric material.

Release Layer Paste

A release layer paste was obtained by diluting the above dielectricgreen sheet paste by ethanol/toluene (55/10) with 2 times at a weightratio.

Adhesive Layer Paste

The above dielectric green sheet paste, but not containing thedielectric particles and release agent, was diluted by toluene with 4times at the weight ratio and used as an adhesive layer paste.

Internal Electrode Paste (Electrode Layer Paste to be Transferred)

Next, an internal electrode paste was obtained by kneading a materialhaving the blending ratio below by a three-roll to make slurry. Namely,100 parts by weight of Ni particles having an average particle diameterof 0.4 μm were added with 40 parts by weight of an organic vehicle(obtained by dissolving 8 parts by weight of a polyvinyl butyral resinas a binder in 92 parts by weight of terpineol) and 10 parts by weightof terpineol, and kneaded by a three-roll and made to be slurry, so thatan internal electrode paste was obtained.

Production of Blank Pattern Layer Printing Paste

The same ceramic powder and subcomponent additives as those used for thegreen sheet paste were prepared to have the same blending ratio.

The ceramic powder and subcomponent additives (150 g) was added with anester based polymer dispersant (1.5 g), terpineol (5 g) and acetone (60g), and dioctyl phthalate (5 g) as a plasticizer and mixed for fourhours. Next, the mixture is added with 8% lacquer (8 wt % of polyvinylbutyral and 92 wt % of terpineol with respect to the total amount of thelacquer) of BH6 made by Sekisui Chemical Co., Ltd. (a polyvinyl butyralresin having a polymerization degree of 1450 and butylaration degree of69 mol %±3%) by an amount of 120 g and mixed for 16 hours. After that,acetone as an excess solvent was removed and terpineol was added by 40to 100 g for adjusting the viscosity, so that a paste was produced.

Formation of Green Sheet and Transfer of Adhesive Layer and ElectrodeLayer

First, by using the above dielectric green sheet paste, a green sheethaving a thickness of 1.0 μm was formed on a PET film (second supportingsheet) by using a wire bar coater. Next, the above release layer pastewas applied to another PET film (first supporting sheet) by a wire barcoater and dried to form a release layer of 0.2 μm.

On the surface of the release layer, an electrode layer 12 a and a blankpattern layer 24 were formed. The electrode layer 12 a was formed to bea thickness of 1.2 μm by the printing method using the above internalelectrode paste. The blank pattern layer 24 was formed to be a thicknessof 1.2 μm by the printing method using the above dielectric green sheetpaste.

Also, an adhesive layer 28 was formed on another PET film (thirdsupporting sheet). The adhesive layer 28 was formed to be a thickness of0.1 μm by using the above adhesive layer paste by a wire bar coater.

First, on the surface of the electrode layer 12 a and the blank patternlayer 24, the adhesive layer 28 was transferred by the method shown inFIG. 2. At the time of transferring, a pair of rolls were used, thepressing force was 1 MPa and the temperature was 80° C. It was confirmedthat the transfer was preferably performed.

Next, by the method shown in FIG. 3, the internal electrode layer 12 aand the blank pattern layer 24 were bonded with (transferred to) thesurface of the green sheet 10 a via the adhesive layer 28. At the timeof transferring, a pair of rolls were used, the pressing force was 1 MPaand the temperature was 80° C. It was confirmed that the transfer waspreferably performed.

Next, by the method shown in FIG. 4 to FIG. 6, the internal electrodelayers 12 a and green sheets 10 a were successively stacked and,finally, it was possible to stack 5 internal electrode layers 12 a.

Transferring was performed respectively on 20 same samples, and a ratio(good product rate) of those without any cracks and pinholes on thetransferred electrode layer and breaking on the green sheet wasmeasured. 95% or higher was determined @, 60 to 95% was determined o,and 60% or lower was determined x. The results are shown in Table 1.Note that when determining the good product rate, deformation of thesupporting sheet (PET sheet) was also evaluated and deformed ones wereevaluated defective. TABLE 1 Pressing Pressing Green Sheet Adhesive GoodProduct Force Temperature Thickness Layer Ratio (MPa) (° C.) (μm)Thickness (μm) Transferability n = 20(%) Example 1 1 80 1.0 0.1 ⊚ 100Example 2 0.2 80 1.0 0.1 ◯ 65 Example 2 0.5 80 1.0 0.1 ⊚ 95 Example 2 280 1.0 0.1 ⊚ 100 Example 2 5 80 1.0 0.1 ◯ 90 Example 2 10 80 1.0 0.1 ◯90 Example 2 15 80 1.0 0.1 ◯ 80 Example 3 0.5 40 1.0 0.1 ◯ 65 Example 30.5 50 1.0 0.1 ◯ 80 Example 3 0.5 60 1.0 0.1 ⊚ 95 Example 3 0.5 70 1.00.1 ⊚ 100 Example 3 0.5 90 1.0 0.1 ⊚ 95 Example 3 0.5 100 1.0 0.1 ◯ 85Example 3 1 120 1.0 0.1 X 50 Comparative 15 100 1.0 0.1 X 0 Example 2Example 4 1 80 1.0 0.1 ◯ 75 Example 5 1 80 1.0 0.1 ◯ 65 Example 6 1 801.0 0.1 ◯ 65 Example 7 1 80 1.0 0.01 X 10 Example 7 1 80 1.0 0.05 ◯ 60Example 7 1 80 1.0 0.3 ⊚ 100 Example 7 1 80 1.0 0.5 ⊚ 100 *1*1: Crackes were observed on sintered body after stacking 30 layers andfiring.

EXAMPLE 2

Other than changing the pressing force at the time of transferring in arange of 0.2 to 15 MPa, an internal electrode layer 12 a and blankpattern layer 24 were bonded with (transferred to) a surface of thegreen sheet 10 a in the same way as in the example 1. Transferabilitywas evaluated in the same way as in the example 1. The results are shownin Table 1.

As shown in Table 1, it was confirmed that the pressing force at thetime of transferring is preferably 0.2 to 15 MPa, more preferably 0.2 to6 MPa and particularly preferably 1 to 3 MPa.

EXAMPLE 3

Other than changing the heating temperature at the time of transferringin a range of 40 to 120° C., an internal electrode layer 12 a and blankpattern layer 24 were bonded with (transferred to) a surface of thegreen sheet 10 a in the same way as in the example 1. Transferabilitywas evaluated in the same way as in the example 1. The results are shownin Table 1.

As shown in Table 1, it was confirmed that the temperature at the timeof transferring was preferably 40 to 100° C. or so, and more preferably90° C. or lower and 60° C. or higher.

COMPARATIVE EXAMPLE 1

Other than not forming the adhesive layer 28, the internal electrodelayer 12 a and the blank pattern layer 24 were bonded with (transferredto) the surface of the green sheet 10 a in the same way as in theexample 1.

Transferring was not attained at all and 20 same samples came unstuck.

COMPARATIVE EXAMPLE 2

Other than not forming the adhesive layer 28 and changing the pressingforce to 15 MPa and the temperature to 100° C. at the time of bonding(transferring) the internal electrode layer 12 a and the blank patternlayer 24 with a surface of the green sheet 10 a, the internal electrodelayer 12 a and the blank pattern layer 24 were bonded with (transferredto) the surface of the green sheet 10 a in the same way as in theexample 1.

Results of evaluating transferability in the same way as in the example1 are shown in Table 1. As shown in Table 1, when the adhesive layer 28is not formed, it was confirmed that the transferability was poor eventhough the pressing force was increased.

COMPARATIVE EXAMPLE 3

Other than forming the adhesive layer 28 to be a thickness of 0.1 μmdirectly on the surface of the electrode layer 12 a and the blankpattern layer 24 by a wire bar coater, the internal electrode layer 12 aand the blank pattern layer 24 were bonded with (transferred to) thesurface of the green sheet 10 a in the same way as in the example 1.

Components of the adhesive layer soaked in the electrode layer or greensheet and adhesiveness on the surface was not able to be improved, sothat transfer was not attained. Namely, it was confirmed that thetransferability was unable to be improved when the adhesive layer wasformed by a method other than the transfer method.

EXAMPLE 4

Other than replacing the binder resin of the adhesive layer paste by anacrylic resin, the internal electrode layer 12 a and the blank patternlayer 24 were bonded with (transferred to) the surface of the greensheet 10 a in the same way as in the example 1.

The results of evaluating transferability in the same way as in theexample 1 are shown in Table 1. As shown in Table 1, it was confirmedthat the transferability was a little inferior to that in the example 1but was still preferable.

EXAMPLE 5

Other than replacing the binder resin of the adhesive layer paste by anethyl cellulose resin, the internal electrode layer 12 a and the blankpattern layer 24 were bonded with (transferred to) the surface of thegreen sheet 10 a in the same way as in the example 1.

The results of evaluating transferability in the same way as in theexample 1 are shown in Table 1. As shown in Table 1, it was confirmedthat the transferability was a little inferior to that in the example 1but was still preferable.

EXAMPLE 6

Other than replacing the binder resin of the blank layer paste by anethyl cellulose resin, the internal electrode layer 12 a and the blankpattern layer 24 were bonded with (transferred to) the surface of thegreen sheet 10 a in the same way as in the example 1.

The results of evaluating transferability in the same way as in theexample 1 are shown in Table 1. As shown in Table 1, it was confirmedthat the transferability was a little inferior to that in the example 1but was still preferable.

EXAMPLE 7

Other than changing the thickness of the adhesive layer to 0.01 to 0.5μm, the internal electrode layer 12 a and the blank pattern layer 24were bonded with (transferred to) the surface of the green sheet 10 a inthe same way as in the example 1.

The results of evaluating transferability in the same way as in theexample 1 are shown in Table 1. Note that, in Table 1, thetransferability was preferable when the thickness of the adhesive layerby the transfer method was 0.5 μm, but cracks were observed on a firedbody when 30 layers were stacked and fired. On the other hand, when theadhesive layer was 0.3 μm or thinner, cracks were not observed on afired body when 30 layers were stacked and fired.

From the above results, as shown in Table 1, it was confirmed that thethickness of the adhesive layer formed by the transfer method waspreferably 0.02 to 0.3 μm, and more preferably 0.1 to 0.3 μm.

1. A production method of an electronic device having an internalelectrode, comprising the steps of: forming a release layer on a surfaceof a first supporting sheet; forming an electrode layer on a surface ofsaid release layer; pressing said electrode layer against a surface of agreen sheet to bond said electrode layer with the surface of said greensheet; stacking the green sheets bonded with said electrode layer toform a green chip; and firing said green chip; wherein before pressingsaid electrode layer against the surface of said green sheet, anadhesive layer is formed on a surface of said electrode layer or asurface of said green sheet by a transfer method.
 2. The productionmethod of an electronic device having an internal electrode as set forthin claim 1, wherein: to form said green chip, a step of pressing anotherelectrode layer to be bonded against an opposite surface of theelectrode layer side of the green sheet bonded with said electrode layerso as to bond the electrode layer via an adhesive layer formed by thetransfer method, and a step of pressing the electrode layer againstanother green sheet so as to bond via an adhesive layer formed by thetransfer method are repeated.
 3. The production method of an electronicdevice having an internal electrode as set forth in claim 1, wherein: toform said green chip, a step of pressing another green sheet to bebonded against a surface on the electrode layer side of the green sheetbonded with said electrode layer so as to bond the green sheet via anadhesive layer formed by the transfer method, and a step of pressinganother electrode layer against the green sheet so as to bond via anadhesive layer formed by the transfer method are repeated.
 4. Theproduction method of an electronic device having an internal electrodeas set forth in claim 1, wherein said green sheet is formed on a surfaceof a second supporting sheet in a releasable way and, after saidelectrode layer is bonded with a surface of said green sheet, saidsecond supporting sheet is released from the surface of said greensheet.
 5. The production method of an electronic device having aninternal electrode as set forth in claim 1, wherein said adhesive layeris formed on a surface of a third supporting sheet in a releasable wayfirst and pressed against a surface of said green sheet or a surface ofsaid electrode layer so as to be bonded.
 6. The production method of anelectronic device having an internal electrode as set forth in claim 1,wherein a thickness of said adhesive layer is 0.02 to 0.3 μm.
 7. Theproduction method of an electronic device having an internal electrodeas set forth in claim 1, wherein said electrode layer is formed to be apredetermined pattern on a surface of said release layer, and a blankpattern layer having substantially the same thickness as that of saidelectrode layer is formed on a surface of the release layer not formedwith the electrode layer.
 8. The production method of an electronicdevice having an internal electrode as set forth in claim 7, whereinsaid blank pattern layer includes substantially the same dielectrics asthat composing said green sheet.
 9. The production method of anelectronic device having an internal electrode as set forth in claim 7,wherein said blank pattern layer includes substantially the same binderas that of said green sheet.
 10. The production method of an electronicdevice having an internal electrode as set forth in claim 1, whereinsaid release layer includes substantially the same dielectrics as thatcomposing said green sheet.
 11. The production method of an electronicdevice having an internal electrode as set forth in claim 10, whereinsaid release layer includes substantially the same binder resin as thatincluded in said green sheet.
 12. The production method of an electronicdevice having an internal electrode as set forth in claim 1, whereinsaid adhesive layer includes substantially the same binder resin as thatincluded in said green sheet.
 13. The production method of an electronicdevice having an internal electrode as set forth in claim 1, whereinsaid electrode layer includes substantially the same binder resin asthat included in said green sheet.
 14. The production method of anelectronic device having an internal electrode as set forth in claim 9,wherein said binder resin includes a butyral based resin.
 15. Theproduction method of an electronic device having an internal electrodeas set forth in claim 1, wherein a thickness of said green sheet is 3 μmor thinner.
 16. The production method of an electronic device having aninternal electrode as set forth in claim 1, wherein a thickness of saidrelease layer is not thicker than a thickness of said electrode layer.17. The production method of an electronic device having an internalelectrode as set forth in claim 1, wherein a pressure at the time ofbonding said electrode layer with a surface of said green sheet is 0.2to 15 MPa.
 18. The production method of an electronic device having aninternal electrode as set forth in claim 1, wherein a pressingtemperature at the time of bonding said electrode layer with a surfaceof said green sheet is 40 to 100° C.